Ou Xiaoli, director-general of the National Development and Reform Commission's social development department, described the supporting rules as the central plank of efforts to build a "fertility-friendly society".
To achieve that, he said one priority is to make it easier and more affordable to care for young children.
That's because young couples have long relied on retired parents to care for infants and toddlers until they are old enough to attend kindergarten, usually at age 3.
But the latest census data showed that Chinese families had an average of 2.62 members last year, down from 3.1 in the previous census a decade earlier.
Experts said the number reflects young people's tendency to live apart from their parents and in-laws, and the trend is weakening the family's traditional function of child care.
Yang Wenzhuang, director-general of the National Health Commission's population and family department, said China has around 42 million children younger than 3.
Demand for day care is strong among one-third of the toddlers' families, but less than 6 percent have had access to such services, he said.
The central government released a guideline in 2019 to bolster the provision of day care services for such children and included it in its latest five-year plan, he added.
Workplaces have also been encouraged to run in-house day care facilities, Yang said, adding that the commission will step up oversight to ensure safety.
Lyu Yugang, director-general of the Ministry of Education's basic education department, said the coverage of government-subsidized kindergartens has grown rapidly lately, reaching 84.7 percent by the end of last year.
He said that was a "leap forward" given that parents had complained for years that kindergarten enrollment was difficult and private ones were expensive.
Since 2017, the ministry has asked schools to offer after-school services to remedy the mismatch between parents' work schedules and schooling, which ends at around 3 pm each weekday for primary schools.
Despite the policy shift, the resolution has pledged continuous efforts to protect the rights of families who only have one child.
Those include continuing the reward and assistance system, which provides subsidies both for families with one child and rural families with two daughters that were born before the introduction of the second-child policy in 2016.
Yu said: "This shows the Party and the State have high regard for the contributions made by one-child families."